Find missing lengths of x, y, and a?

The management of a supermarket wants to adopt a new promotional policy of giving a free gift to every customer who spends more than a certain amount per visit at this supermarket. the expectation of the management is that after this promotional policy is advertised, the expenditures for all customers at this supermarket will be normally distributed with a mean of $95 and a standard deviation of $20. if the management wants to give free gifts to at most 10% of the customers, what should the amount be above which a customer would receive a free gift?

In order to be invited to tutoring or extension activities a students performance 20 point higher or lower than average for the

The first term of a sequence is -12. the recursive formula for the sequence is an = an-1 + 9. what are the next 3 terms in the sequence? a) -3, -15, -27 b) -3, 6, 15 c) -3, -6, -3 d) -3, -6, 3